Use Realtime TTS in your multilingual applications, with support for 100+ languages and cross-lingual capabilities that let you reuse a single voice across multiple languages.Documentation Index
Fetch the complete documentation index at: https://docs.inworld.ai/llms.txt
Use this file to discover all available pages before exploring further.
As a more capable model, Realtime TTS-2 (
inworld-tts-2) is better suited for multilingual applications, offering better pronunciation, more accurate intonation, and more natural-sounding speech. Please share any feedback with us in Discord.Supported languages
inworld-tts-2, inworld-tts-1.5-max, and inworld-tts-1.5-mini support the following languages:
Arabic (ar) | Chinese (zh) | Dutch (nl) | English (en) |
French (fr) | German (de) | Hebrew (he) | Hindi (hi) |
Italian (it) | Japanese (ja) | Korean (ko) | Polish (pl) |
Portuguese (pt) | Russian (ru) | Spanish (es) |
inworld-tts-2 also offers experimental support for the following languages:
Afrikaans (af) | Albanian (sq) | Amharic (am) | Antankarana Malagasy |
Armenian (hy) | Assamese (as) | Azerbaijani (az) | Bagirmi Fulfulde |
Basque (eu) | Belarusian (be) | Bengali (bn) | Bulgarian (bg) |
Burmese (my) | Cantonese (yue) | Catalan (ca) | Cebuano (ceb) |
Croatian (hr) | Czech (cs) | Danish (da) | Eastern Bolivian Guaraní |
Eastern Yiddish (yih) | Egyptian Arabic (arz) | Estonian (et) | Filipino (fil) |
Finnish (fi) | Galician (gl) | Garhwali (gbm) | Georgian (ka) |
Greek (el) | Gujarati (gu) | Gulf Arabic (afb) | Haitian Creole (ht) |
Hijazi Arabic (acw) | Hungarian (hu) | Icelandic (is) | Indonesian (id) |
Javanese (jv) | Kannada (kn) | Kazakh (kk) | Konkani (kok) |
Lao (lo) | Latvian (lv) | Libyan Arabic (ayl) | Lithuanian (lt) |
Luxembourgish (lb) | Macedonian (mk) | Maithili (mai) | Malagasy (mg) |
Malay (ms) | Malayalam (ml) | Marathi (mr) | Masikoro Malagasy |
Mongolian (mn) | Najdi Arabic (ars) | Nepali (ne) | Northern Betsimisaraka Malagasy |
Northern Uzbek (uzn) | Norwegian Bokmål (nb) | Norwegian Nynorsk (nn) | Odia (or) |
Omani Arabic (acx) | Orma | Pashto (ps) | Persian (fa) |
Piedmontese (pms) | Plateau Malagasy | Pular | Pulaar |
Punjabi (pa) | Romanian (ro) | Serbian (sr) | Sindhi (sd) |
Sinhala (si) | Slovak (sk) | Slovenian (sl) | Southern Betsimisaraka Malagasy |
Swahili (sw) | Swedish (sv) | Tamil (ta) | Telugu (te) |
| Tesaka Malagasy | Thai (th) | Tunisian Arabic (aeb) | Turkish (tr) |
Ukrainian (uk) | Urdu (ur) | Uzbek (uz) | Vietnamese (vi) |
Võro (vro) | Welsh (cy) |
To test an experimental language, clone a voice in that language
Cross-lingual support
Realtime TTS-2 supports cross-lingual synthesis, where the same voice can be used across multiple languages. Depending on the voice and language, the voice may retain the accent of the original voice language when speaking a different language (e.g., a French voice may speak English with a French accent). TTS-1.5 performs optimally when synthesizing text in the same language as the voice prompt. You’ll achieve the best quality, pronunciation, and naturalness by matching the voice’s prompt language to your text content. For the most natural, consistent cross-lingual results, we recommend specifying the language to synthesize in and localizing the voice.Specifying a language
Use thelanguage field to tell the model which language the voice should speak the text in. When set, the service will:
- Apply text normalization (if enabled) for the target language (e.g., speaking numbers in the target language).
- Use the voice’s localized prompt for that language, if one exists. If no localized prompt is available, the model will be steered to speak in the target language.
language is omitted, the original voice prompt is used and the language for normalization (if enabled) is auto-detected from the input text.
If you are sending short requests with only numbers or dates (e.g., 123-456-7890), auto-detection may not have enough context to detect the right language. In those cases, we recommend specifying a language for most consistent results.
Voice Localization
Voice localization can help produce more consistent, native-sounding speech in a target language. It is supported for all Inworld TTS models.Open the Voices page in Portal
In Inworld Portal, go to Voices and select the My voices tab. Hover over an English voice to open its details panel on the right.
Voice localization is currently only supported for voices where the original audio was in English. Support for additional languages is coming soon.
Choose a target language
Pick a target language from the dropdown and click Localize, which will start generating localized prompt candidates. This may take up to 2 minutes.
Review candidates
After generation, you’ll see a few localized prompt candidates. Listen to each and pick the one that sounds most natural and native, then click Save.If none sound right, you can click Regenerate. You may want to change the script before regenerating, since the script influences the generated voice.
Next steps
Voice Cloning
Clone a voice once and reuse it across languages.
Custom Pronunciation
Use IPA notation to control pronunciation of proper nouns and edge cases.